Adjustable ring gauge



Jan. 29, 1952 HOHWART ET AL 2,583,738

ADJUSTABLE RING GAUGE Filed Jan. 31, 1946 INVENTORS. gee/ c floZM/ari,gives? 77%5/4 4f Patented Jan. 29, 1952 ADJUSTABLE RING GAUGE GeorgeHohwart and Ernest F. Hohwart, Detroit, Mich., assignors to N. A.Woodworth Company, Ferndale, Mich., a corporation of MichiganApplication January 31, 1946, Serial No. 644,602

This invention relates broadly to new and useful improvements inadjustable ring gages and more particularly to a gage of this typehaving novel means of adjusting the size of the gage body.

An important object of the present invention is to provide an adjustablering gage that can be easily and accurately adjusted.

Another object of the invention is to provide novel adjusting means thatis adaptable for either plain or thread ring gages.

Still another object of the invention is to provide a ring gage of theabove-mentioned character in which the adjusting means applies acontracting force uniformly against the gage body and in such mannerthat the gaging bore maintains absolute circularity in all adjustedpositions of the body.

Yet another object of the invention is to provide an adjustable ringgage of the above type that can be securely locked in any selectedadjusted position.

Other objects and advantages of the invention will be apparent duringthe course of the following description.

In the drawings forming a part of this specification and wherein likenumerals are employed to designate like parts throughout the same,

Fig. 1 is a side elevational view of an adjust:

able ring gage embodying the invention;

Fig. 2 is a transverse sectional view taken on the line 2--2 of Fig. 1;

Fig. 3 is a sectional view similar to Fig 2 but showing a modified formof the invention;

Fig. 4 is a side elevational view of still another form of theinvention;

Fig. 5 is a transverse sectional view taken on the line 55 of Fig. 4;and

Fig. 6 is a transverse sectional view of still another form of theinvention.

Attention is first directed to Figs. 1 and 2, which show one form ofring gage embodying the invention. The numeral designates an annulargage member or body having a central gaging bore I2 which is adapted toreceive and snugly fit a workpiece to be tested. In so far as thepresent invention is concerned, the member Ill may be adapted fortesting either plain or threaded work; however, a thread ring gage ishere shown by way of illustration, and the bore I2 is provided withinternal screw threads [4.

In order that the member Ill be adjustable, it is provided with theusual radial locking slot l and adjusting slots [8. Locking slot I6extends entirely through the member Ill, and the adjusting slots I8extend inwardly from the periphery but terminate short of the bore l2.As shown in Fig. 1, a number of adjusting slots l8 are provided, andthey preferably are arranged in substantially equispaced relation aroundthe member lll. These latter slots increase the 1 Claim. (Cl. 33-178)flexibility of the body member and assure more or less uniform expansionand contraction whereby to maintain absolute circularity of the bore [2in all adjusted positions of the body.

Surrounding the body member [0 and spaced radially outwardly from theoppositely tapered, essentially fiat, annular peripheral body surfaces20 and 22 is an annular and rigid adjusting member 24. The latterpreferably is of subtantially the same width as the body In and isintegrally attached to a clamping ring 26 which extends radiallyinwardly therefrom and is approximately one half as wide as the body.The inner annular surface 28 of ring 26 is tapered axially outwardly andsnugly fits the body surface 20. Interposed between the other bodysurface 22 and the adjusting member 24 is a separate rigid clamping ring30 which co-operates with the integral ring 26 to contract the gage bodymember 10. Ring 30 is provided with external screw threads 3! whichengage the internal threads 32 of adjusting member 24, and its innersurface 34 is outwardly tapered to mate with the body surface 22. Whenthe body H] is fully expanded, the inner radial faces of locking rings26 and 3B are spaced apart so that the latter can move axially for alimited distance.

In practice, the gaging bore I2 is made as large as the largest work tobe tested, and the gage body I0 is adjusted to fit slightly smallerworkpieces or to compensate for wear. To set the gage, a master threadgage plug having the same external diameter as the Work to be tested isscrewed into the bore l2, and the clamping ring 30 is tightened in theadjusting member 24 and against the body l0. As the locking ring 30 ismoved axially inwardly by threads 3i and 32, it pulls the integral ring26 solidly against the body surface 20 and presses its inner surface 34solidly against the body surface 22. Pressure is thus appliedsimultaneously and equally against the surfaces 20 and 22 to effect auniform contraction of the body l0.

Any suitable means can be used to rotate the locking ring 30. One meanshere shown by way of illustration merely comprises annular series ofsockets 36 in the outer radial faces of the clamping rings 26 and 30,and, when this construction is employed, "the only equipment required toset the gage is a couple of spanners having projecting lugs which fit inthe sockets 36.

The usual procedure is to tighten clamping ring 30 until the body [0 iscontracted sufliciently to prevent movement of the master plug. Atapered locking pin 40 is then driven into the looking slot [6 to expandthe body. If desired, the walls of the slot may be provided withshallow, correspondingly tapered channels 38 which accommodate the pin40. Pressure exerted by this pin against the walls of the slot IGexpandsthe body l sufficiently so that the master plug can be turned: withprecisely the desired amount of resistance from the gage bore l2. Sincelocking pin 40 is driven forcibly into the slot l6, it is frictionallyheld in place by the walls of the slot. Also, expansion of the body l0presses the peripheral surfaces 20 and 22 radially outwardly against theconfronting and mating surfaces 28 and 34 so that it is substantiallyimpossible to move any part of the gage until thelocking pin 40 isremoved.

Preferably, the locking slot 16 is provided with countersinks 42 whichopen through opposite sides of the body and radially relieve theterminal portions of locking pin 40. As a result, the expanding forceexerted by pin 40 against the walls of the locking slot I6 is confinedsubstantially to the middle of the body. This arrangement prevents, oratleast inhibits, any tendencyof the body to become distorted due toimproper fits betweenthe pin and the walls of locking slot I 6.

The form of the invention shown in Fig. 3 is identical in constructionand operation to the form hereinabove described, except that theclamping ring 26 is discrete and separate from the adjusting member 24.The internal screw thread 32 is extended entirely across the adjustingmember to engage external screw threads 44 on the periphery of clampingring 26. Thus, the ring 26 is movable independently of theadjusting-member 24 and the companion clamping ring 30. In fact it issimilar in all respects to the clamping ring 30 and is tightenedsimultaneously therewith to radially contract the body I6.

The form of the invention shown in Figs. 4 and 5 is identical to theform shown in Fig. 3, except that the threaded connections and beveledsurfaces are transposed and the clamping rings 26 and 30 are splitradially so that they are contractible'to transmit thrust fromthe-adjusting faces 48 and 56. The clamping rings are screwed onto thegage body 10, as shown in Fig.5, and

have inwardly tapered, peripheral surfaces52 and .i

54 which mate with correspondingly tapered inner surfaces 56 and 58respectively on the adjusting member 24. As best shown in Fig. 4, theclamping rings 26 and 36 have radial through slots 66 which make themcontractible and expansible, They are also provided with a plurality ofradial adjusting slots 62 in the same manner as the gage body H], whichslots increase their flexibility and cause them to transmit radiallycompressive forces more or less uniformly against the body I0. While sixadjusting slots 62 are here shown, it will be readily appreciated thatany desired number maybe provided. In general, the number of adjustingslots required to make the clamping rings sufliciently flexiblevariesaccording to the size of the-rings and the materials from whichthey are made.

From the foregoing it will be apparent that, when they are tightened onthe body In and against the tapered surfaces 56 and 58, clamping rings26 and 30 are securely held in the selected adjusted position by thethreaded connections with the body and pressure against surfaces 52and'54 exerts a radial-component'of force which tends to, contract therings. Since the clamping rings snugly fit the gage body [0, they manifestly cannot contract without also contracting the body. Thus,tighteningof the clamping rings 26 and 36 contracts the gage body 10;and, conversely, loosening of the clamping rings permits the gage bodyto expand.

The form of the invention shown in Fig. 6 is identical to the form shownin Figs. 1 and 2,'except that the clamping ring 26 comprises relativelythin, integrally connected, radial and axial annular flange portions 64and 66 instead of the relatively massive and heavy piece of metal shownin'Fig. 2. The radial flange portion 64 is integral with the adjustingmember 24, and the axial flange portion 66 is outwardly tapered so thatits inner surface 68 mates with and snugly fits the body surface 20.

Manifestly, the form of the invention shown in Fig. 6 operates in thesame manner as the form shown in Figs. 1 and 2 to adjust the gage body10. The main advantage of the latter form is:that a substantial savingin weight is achieved without 7 sacrificing strength or efliciency ofoperation. The larger size gages are quite heavy, and weight is animportant factor, since they must be handled manually during testing ofthe workpieces.

It is to be understood that the forms of the invention herewith shownand described are to be taken as preferred examples of the same, andthat various changes in the size, shape, and arrangesurface which matesand seats solidly against one tapered surface of the gaging member andthe outer axial portion having an internally screwthreaded annularsurface which surrounds and is spaced circurnferentially from the othertapered surface of the gaging member; and a rigid clamping ring confinedbetween the gaging member and the last-mentioned surface of theadjusting member, said ring provided with an inner tapered surface whichmates and seats solidly againstthe confronting tapered surface ofthegaging member and external screw threads which engage'the internal screwthreads of said adjusting member.

GEORGE HOI-IWART.

ERNEST F. 'HOHWART.

REFERENCES CITED The following references are of record in the file ofthis patent." I I b H UNITED STATES PATENTS Number ,Name Date 473,582Keiper Apr. 26, 1892 525,775 Wainwright Sept. 11, 1394 687,864 Smyth'Dec, 3, 1961 1,282,392 Doonaevski Oct. 22, 1918 2,356,133 7 Vanden-Kieboom Aug. 22, 194.4

2,413,566 Hohwart et a1, Dec; 31, 1946 V FOREIGN PATENTS Number. CountryDate

